Transition from a continental to an oceanic rift: geology and biogeochemistry of the Northern Red Sea

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Understanding the processes that occur during the transition from a continental to an oceanic rift, the earliest stages of seafloor spreading and the formation of passive margins is a major challenge in the Earth Sciences. We address this challenge with a research project on the geology and biogeochemistry of the northern Red Sea Rift. The Red Sea/Gulf of Aden/East African Rift system provides an ideal natural setting to study the continental to oceanic rift transition. We propose a 35 days expedition to the northern Red Sea with the Italian research vessel Urania. The objectives are to study (a) the northernmost (presumably youngest) throughs with truly "oceanic" crust, and their transition to thinned/stretched continental crust; (b) a fracture zone intersecting the Red Sea (Zabargad F.Z.), where the earliest stages in the development of the large oceanic transforms can be observed, and where the North-propagating Red Sea oceanic rift appears to impact at present. The work will include multibeam, magnetometric, gravimetric and seismic reflection surveys, rock and sediment sampling and water sampling aboxe axial hydrothermal vents. The project, in addition to processing and interpreting the geophysical data obtained at sea, will involve also a large analytical program on the geochemistry of igneous rocks and of hydrothermal fluids. The work will clarify tectonic and petrological aspects of the transition form continental to oceanic rift and of the formation of passive margins, and will also address problems of sedimentation in an embryonic ocean and of biogeochemistry in axial hydrothermal cells. The project implies collaboration among Italian, French, German and British scientists and Institutions.